1. Department of Surgery (H.M., M.G.B., A.B.M., S.B., A.K., S.O., R.S.D.H., D.L.S., E.L.B.), Johns Hopkins University School of Medicine, Baltimore, MD.
2. Department of Epidemiology, Johns Hopkins University School of Public Health, Baltimore, MD (A.B.M., C.M., D.L.S.).
3. Department of Medicine (C.M.), Johns Hopkins University School of Medicine, Baltimore, MD.